The flight was QF31 and had 258 passengers on board, with four pilots and 21 cabin crew, Qantas said.

The plane was an Airbus A380 superjumbo and engine number four suffered "an engine oil defect", a spokeswoman said.

The problem comes exactly one year after a mid-air engine blast forced an emergency landing of a Qantas A380 jet in Singapore.

Last year's emergency landing resulted in Qantas grounding its entire fleet of A380 aircraft, each of which is powered by four Rolls Royce engines, for safety checks.

The latest edition of Business Daily speaks to Bob Pozen, a senior lecturer at Harvard University and a former adviser to Republican Presidential contender Mitt Romney, about possible solutions to the debt problems of the US.